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1.
区域生态环境质量评价研究进展与展望   总被引:5,自引:0,他引:5  
提高生态环境质量已成为当前人民保障生活质量的迫切需求,进行生态环境质量评价是生态建设和保护环境的重要基础工作。通过对国内外文献进行统计和分析,得出如下结论。①形式方面:20年来国际国内在生态环境质量评价方面进行了大量的研究工作且10年来加速上升,研究成果主要以期刊、学位论文、会议论文和专著等媒介展现。②内容方面:同期相比,国外的研究主要集中于各专题如水环境、气环境和土壤环境的分析及某些典型的区域问题解决。我国虽起步稍晚,在国家和省部级政府的倡导与支持下发展迅速且紧跟国际前沿,以基础和应用研究、工程技术、政策指导和行业技术指导等为导向,体现出服务于经济发展、注重实践和方法创新的特色。③手段方面:遥感和地理信息系统等高技术手段在环境质量评价方面发挥了很大的作用,有巨大的潜力和广阔的前景,发达国家更着重于环境因素的深入定量分析遥感反演,发展中国家更着重于宏观层面上的信息获取和综合质量评价应用。④内涵方面:现有的工作可归为生态环境质量评价的生态环境遥感信息获取、评价指标体系构建、不同尺度对象的评价、评价技术手段和方法模型探索以及评价思路视野目标几个侧重面。⑤局限方面:通过纵观近期的研究进展和发展趋势分析,总结出现阶段的局限主要体现在评价指标选择偏主观、评价模型偏模糊、评价对象对象尺度和属性认识偏笼统和定量遥感信息的应用不足等问题。⑥展望方面:建议今后的研究多注重于人口数量和结构对生态环境的影响、分析各指标因素间的内在联系与影响机理、充分发掘和利用遥感定量信息、评价模型基于时代经济特色和对象客观条件和功能的理想值参照等,以期待提高生态环境质量评价工作的效率和深度。  相似文献   

2.
根据中国可持续发展信息共享系统建设的要求,针对全国农村生态环境质量的信息特征,描述了“全国农村生态环境质量信息共享系统”的设计背景、系统总体结构、数据组织形式以及信息表达方式,并探讨了实现信息共享系统的结构化设计、系统网络的集成式服务模型、动态网页制作、元数据库构建、统计信息的空间化表达方法、空间统计分析和信息共享安全保障等信息共享的关键技术途径。  相似文献   

3.
《Ecological modelling》2007,208(1):80-90
Information indices from Ecosystem Network Analysis (ENA) can be used to quantify the development of an ecosystem in terms of its size and organization. There are two types of indices, i.e. absolute indices that describe both the size and organization of ecosystem (Total System Throughput (TST)—system size, Ascendancy (A)—size of organized flows and Development Capacity (C)—upper limit for A, Overhead (L)—size of unorganized flows) and relative indices that describe only the organization (Average Mutual Information (AMI = A:TST), Flow Diversity (H = C:TST), Relative Overhead (RL = L:TST)).It is theorized that environmental stress impair the ecosystem development and that the effect of stress can be quantified with the ENA information indices. Here we applied ENA on a case of environmental stress in a terrestrial ecosystem, i.e. soils that have endured long-term exposure to elevated copper concentration and altered pH.The absolute indices showed an unexpected pattern of response to pollution, suggesting that ecosystems in polluted soils are more active and better organized than these in unpolluted soils. The relative indices, alternatively, responded to pollution as predicted by theory, i.e. with decrease of stress (pollution level) the level of specialization increased (increase of AMI) and losses of energy, e.g. due to respiration, decreased (decrease of Overhead). The diversity and evenness of flows showed hump-backed relationship with stress. Less polluted soils appeared to be less vulnerable to external disturbances and more efficient in processing energy (higher Relative Ascendancy (RA = A:C)) than polluted soils. The relative information indices were rigid to changes in values of assumed parameters. The relative indices, opposite to absolute indices, appeared to be useful as indicators of environmental stress on the ecosystem level.  相似文献   

4.
Summary In the monogamous least auklet (Aethia pusilla, Alcidae) both males and females have three highly variable ornamental traits (facial plumes, a colourful bill and a knob-like bill ornament) and both sexes perform courtship displays. To assess whether mating preferences could be related to the expression of these ornaments, we performed model presentation experiments in which we varied the bill colour and the size of both the bill ornament and the facial plumes. Auklets reacted to models that had brighter red bills and accentuated facial plumes with more frequent sexual displays than to models with average bills and plumes. We conclude that these two ornamental traits are likely to be favoured by sexual selection through mating preferences. In general, however, ornaments were weak predictors of individual quality. Multiple regression indicated that all ornaments taken together explained a small (R 2 = 0.07) but significant proportion of the variability in adult body condition but only in a poor year for reproduction when the birds were in relatively poor body condition and a small proportion of the population bred successfully. The degree of ornamentation was also not related to timing of breeding, chick feeding rate or reproductive success and there was no relationship between adult survival and ornaments. We conclude, therefore, that least auklet ornaments are, at best, weak indicators of quality that may be the result of sexual selection operating only in years when breeding conditions are poor. Offprint requests to: R. Montgomerie  相似文献   

5.
基因污染与生态环境安全   总被引:6,自引:0,他引:6  
论述了基因污染可能对生态环境安全造成的影响。转基因作物有可能污染天然物种的基因库;有可能破坏传统农作物品种的遗传多样性,加速作物种植品种的单一化及基因资源的流失;使抗除草剂作物的基因向野生或半野生植物漂移的可能性加大,有可能创造出“超级杂草”;带有病毒型转基因作物的基因重组,有可能创造出新的植物病毒,导致新的病害;BT转基因抗虫作物分泌的毒素,在食物链中传递,很难加以控制,对非目标生物造成危害,并最终破坏自然生态系统的平衡。文章还从不同角度分析了基因污染的严重性。  相似文献   

6.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and 'sensors' of ecosystem functioning, efficiency, and quality.  相似文献   

7.
Estuaries and coastal lagoons are characterized by a strong spatial and temporal variability of physicochemical characteristics and productivity patterns. In these environments, the magnitude and direction of the ecological responses to inorganic nutrient increase (i.e. eutrophication) are difficult to predict. In the framework of the project, New Indicators of Trophic state and environmental quality of marine coastal ecosystems and transitional environments (NITIDA), we analysed benthic indicators of trophic state, ecosystem efficiency, and environmental quality in four different transitional environments. The trophic state of the sediments was assessed in terms of quantity and bioavailability of sediment organic C pools; ecosystem efficiency was determined in terms of the prokaryote efficiency in exploiting enzymatycally degraded organic C; environmental quality was determined in terms of meiofaunal diversity. Here, we provide a synopsis of the results obtained and a meta-analysis of the scores assessments obtained using the different ecological indicators of environmental quality and demonstrate that trophic state, ecosystem efficiency, and biodiversity in transitional ecosystems are closely linked. We conclude that the assessment of the environmental quality of transitional ecosystems should be based upon a battery of trophic state indicators and ‘sensors’ of ecosystem functioning, efficiency, and quality.  相似文献   

8.
A link between ecological diversity indices and measures of biodiversity   总被引:1,自引:0,他引:1  
The practice of environmental planning and protection frequently necessitates the quantification of ecological diversity. Traditional ‘ecological diversity indices’ are based on the abundances of species present. However, such indices are insensitive to taxonomic or similar differences. With equal species abundances they measure the species richness (species number) only. Conversely, so-called ‘biodiversity indices’ are based on species differences, but are insensitive to the abundance conditions. The quadratic entropy index is the only ecological diversity index, the value of which reflects both the differences ‘and’ abundances of the species. When a species list is given without abundance data, then, using the quadratic entropy index and postulating equal abundances, one gets the only biodiversity index derived from a traditional ecological index of diversity. Its extensive form is identical with the sum of differences or distances between the species present. This index trivially satisfies set monotonicity, an important property for biodiversity indices.  相似文献   

9.
Various pollution indicators of stream Ban-Ganga have been identified on the basis of presence/absence/numerical abundance at various stations. They have been categorized as pollution tolerant, facultative and pollution intolerant groups in relation with the water quality at different stations of stream.  相似文献   

10.
通过梳理目前自然资源和生态环境统计指标(简称生态统计指标)定义和使用情况,发现同内统计指标体系的内容框架有待扩展,指标体系哌待标准化.NPP是衡量生态系统对环境气候响应的重要研究指标,可以考虑作为国内生态统计指标体系的有益补充,因而在列入指标体系之前需要在数据来源和模型方面进行统一和验证.以目前最常使用的NPP光能利用率模型进行适用于研究地区的参数改进,利用RS、GIS技术手段,综合MODIS遥感数据、气象数据(每日降水量、每日气温、日照时间)、一些辅助矢量数据等多源信息,计算出北京地区2008年NPP的月度值和全年累计值,目标是为其进入生态指标体系建立一个系统的数据处理规范,以保证NPP统计的一致性、可行性和有效性.结论:从区位统计结果来看,城市核心区和城市功能拓展区NPP的季节性特征变化不明显,而生态涵养发展区的NPP随着时间变化比较大;从地貌统计结果来看,远山区的NPP值大于平原区,也大于半山区.以上结果与温度、降水的季节性变化和耕地的收种时间具有一致性,证明该处理流程可以作为北京地区NPP量化及空间评估的有效手段.表明,NPP的数据来源稳定,测量模型具有可行性和有效性,可以考虑将该指标纳入自然资源和生态环境统计体系.  相似文献   

11.
生态恢复的环境效应评价研究进展   总被引:3,自引:1,他引:3  
生态恢复环境效应评价即对受损生态系统恢复进行评价,是恢复生态学研究的重点.对生态恢复的环境效应进行科学、客观和准确的评价,不仅是生态恢复的重要组成内容,而且也为生态恢复进一步实施提供重要指导.文章在系统总结生态恢复的环境效应评价研究进展的基础上,归纳了目前生态恢复的环境效应评价研究中存在的问题,对今后生态恢复环境效应评价研究进行了展望:(1)将实地监测结果应用到区域恢复效应评价中;(2)提高生态恢复评价指标体系的普适性与实用性;(3)推进生态恢复效应评价指标贡献的量化研究;(4)加强生态恢复区域效应的研究;(5)重视外来种对生态恢复评价的影响.  相似文献   

12.
Daily JP  Hitt NP  Smith DR  Snyder CD 《Ecology》2012,93(1):17-23
Threshold detection methods are increasingly popular for assessing nonlinear responses to environmental change, but their statistical performance remains poorly understood. We simulated linear change in stream benthic macroinvertebrate communities and evaluated the performance of commonly used threshold detection methods based on model fitting (piecewise quantile regression [PQR]), data partitioning (nonparametric change point analysis [NCPA]), and a hybrid approach (significant zero crossings [SiZer]). We demonstrated that false detection of ecological thresholds (type I errors) and inferences on threshold locations are influenced by sample size, rate of linear change, and frequency of observations across the environmental gradient (i.e., sample-environment distribution, SED). However, the relative importance of these factors varied among statistical methods and between inference types. False detection rates were influenced primarily by user-selected parameters for PQR (tau) and SiZer (bandwidth) and secondarily by sample size (for PQR) and SED (for SiZer). In contrast, the location of reported thresholds was influenced primarily by SED. Bootstrapped confidence intervals for NCPA threshold locations revealed strong correspondence to SED. We conclude that the choice of statistical methods for threshold detection should be matched to experimental and environmental constraints to minimize false detection rates and avoid spurious inferences regarding threshold location.  相似文献   

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Circular or angular variables indicating direction or cyclical time can be of great interest to scientists studying ecology, biology or environmental issues. A common problem of interest in circular data is estimating a preferred direction and its corresponding distribution. This problem is complicated by the so-called “wrap-around effect” on the circle, which exists because there is no natural minimum or maximum. The usual statistics employed for linear data are inappropriate for directional data, as they do not account for its circular nature. Three choices for summarizing the preferred direction (the sample circular mean, sample circular median and a circular analog of the Hodges–Lehmann estimator) are discussed, with examples from environmental and ecological applications. Similar to the linear data case, the relative emphases of different methods sometimes yield different measures of preferred direction in the presence of outliers or lack of symmetry in the original data. Received: November 2003 / Revised: June 2004  相似文献   

15.
《Ecological modelling》2003,159(2-3):223-238
The effectiveness of exergy and specific exergy indices as ecological indicators of the trophic state of lake ecosystems is here tested on a small homogeneous set of shallow lakes which, in spite of their similar nutrient concentrations, morphology and hydrology, show a different trophic state and structure, species composition and abundance. The findings reveal that exergy and specific exergy indices have good negative correlation with phytoplankton biomass and Carlson's trophic state index (TSI) and strong positive correlation to water transparency (the relationship between exergy and eutrophication is clearer if the exergy refers to surface units, rather than volume units) and, hence, that they may be used as ecological indicators of the trophic state of lake ecosystems. The relationship between the responses of the thermodynamic approach and other conventional trophic classification methods (Vollenweider's eutrophication model based on phosphorus loading, the Hillbrich-Ilkowska method and the Vollenweider–OECD classification criterion) previously applied to Lake Trasimeno, was also investigated. The decreasing trend of exergy and specific exergy indices with eutrophication increase appears to be essentially due to the change in species composition and trophic structure, rather than to a different trophic potentiality of the ecosystems investigated. Concerning the identification of the environmental factors responsible for exergy and specific exergy trends, the coherence of the correlation structure between water depth, TSI, exergy and specific exergy indices, suggests that the lake's mean water depth plays a significant role in determining the changes in trophic structure and state (and consequently in exergetic indices) within the set of lakes examined and emphasises the importance of lake morphology in the development and ageing of lake ecosystems.  相似文献   

16.
Many important environmental policies involve some combination of emission controls and ambient environmental quality standards, for instance SO2 emissions are capped under Title IV of the U.S. Clean Air Act Amendments while ambient SO2 concentrations are limited under National Ambient Air Quality Standards (NAAQS). This paper examines the relative performance of emissions standards and ambient standards when the natural environment provides stochastic environmental services for assimilating pollution. For receiving media characterized by greater dispersion in the distribution of environmental services, the optimal emissions policy becomes more stringent, whereas the optimal ambient policy generally becomes more lax. In terms of economic performance, emissions policies are superior to ambient policies for relatively non-toxic pollutants, whereas ambient standards welfare dominate emissions standards for sufficiently toxic pollutants. In the case of combined policies that jointly implement emissions standards and ambient standards, we show that the optimal level of each standard relaxes relative to its counterpart in a unilateral policy, allowing for greater emissions levels and higher pollution concentrations in the environmental medium.  相似文献   

17.
Many important environmental policies involve some combination of emission controls and ambient environmental quality standards, for instance SO2 emissions are capped under Title IV of the U.S. Clean Air Act Amendments while ambient SO2 concentrations are limited under National Ambient Air Quality Standards (NAAQS). This paper examines the relative performance of emissions standards and ambient standards when the natural environment provides stochastic environmental services for assimilating pollution. For receiving media characterized by greater dispersion in the distribution of environmental services, the optimal emissions policy becomes more stringent, whereas the optimal ambient policy generally becomes more lax. In terms of economic performance, emissions policies are superior to ambient policies for relatively non-toxic pollutants, whereas ambient standards welfare dominate emissions standards for sufficiently toxic pollutants. In the case of combined policies that jointly implement emissions standards and ambient standards, we show that the optimal level of each standard relaxes relative to its counterpart in a unilateral policy, allowing for greater emissions levels and higher pollution concentrations in the environmental medium.  相似文献   

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植物对HF气体的敏感性是由多种因素相互作用而成的复杂综合性状,常用于定性描述大气环境质量状况。通过在密闭的培养瓶中一次性通入不同体积浓度的HF气体,以不同浓度HF胁迫下的不同类型植物为例,观察其在不同时间的外观伤害症状和细胞膜透性与HF浓度的关系。结果表明:不同植物对HF的敏感性不同;低浓度长时间和高浓度短时间的症状基本相同;植物细胞膜透性数据即电导率直接反映植物受损程度。综合植物外观症状指标与生理生化指标并赋予不同权重值,建立相对定量化的大气质量生物学指标评价模式,以定量的判断HF气体对植物的伤害,为应用植物监测和评价大气环境质量提供理论和实践依据。  相似文献   

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